The present invention relates to a method of effectively using a CPU (central processing unit) resource of a computer system, and particularly to a method of effectively utilizing a CPU resource which is useless in a virtual machine system.
When a computer user constructs a virtual machine system comprising a plurality of computers on an installed computer (physical machine), the computer user calculates a total CPU power by adding up a CPU power required by each virtual machine, and determines a product model which satisfies the total CPU power from product models that are set stepwise based on the magnitude of the CPU power. Then, the computer user designates a service ratio (service rate) in each virtual machine in response to the CPU power of the determined product model. JP-A-9-81401 describes a function to designate a service rate in each virtual machine.
That is, the total CPU power required by the user is smaller than the CPU power of the installed computer and a CPU power of such difference becomes useless.
It is an object of the present invention to provide a CPU power adjustment method in which the above-mentioned useless CPU power is assigned to a virtual machine which is operated as a monitoring or maintenance virtual machine on the whole system and may be effectively utilized for the operation management.
According to the present invention, in a virtual machine system in which a plurality of virtual machines are operated on a physical machine, the above-mentioned object may be achieved by arbitrarily setting a total CPU power which results from totalizing CPU powers required by each virtual machine within a CPU power of the physical machine, determining a CPU service rate in such a manner that each virtual machine is operated within the set total CPU power and assigning a CPU power of a difference between a CPU power of the physical machine and the total CPU power to a maintenance virtual machine.
Further, according to the present invention, in a virtual machine system in which a plurality of virtual machines are operated on a physical machine, the above-mentioned object may be achieved by totalizing CPU powers required by respective virtual machines, calculating a difference between a CPU power of said physical machine and said total CPU power, and generating a virtual having a CPU power of said difference.